glsl: Implement parser support for atomic counters.

v2: Mark atomic counters as read-only variables.  Move offset overlap
    code to the linker.  Use the contains_atomic() convenience method.
v3: Use pointer to integer instead of non-const reference.  Add
    comment so we remember to add a spec quotation from the next GLSL
    release once the issue of atomic counter aggregation within
    structures is clarified.
v4 (idr): Don't use std::map because it's overkill.  Add an assertion
    that ctx->Const.MaxAtomicBufferBindings <= MAX_COMBINED_ATOMIC_BUFFERS.

Signed-off-by: Francisco Jerez <[email protected]>
Signed-off-by: Ian Romanick <[email protected]>
Reviewed-by: Paul Berry <[email protected]>
Reviewed-by: Ian Romanick <[email protected]>

1 files changed, 15 insertions, 0 deletions

diff --git a/src/glsl/ast.h b/src/glsl/ast.h
index 97905c6a6d1..5c214b6043b 100644
--- a/src/glsl/ast.h
+++ b/src/glsl/ast.h
@@ -385,6 +385,12 @@ struct ast_type_qualifier {
           */
          unsigned explicit_binding:1;
 
+         /**
+          * Flag set if GL_ARB_shader_atomic counter "offset" layout
+          * qualifier is used.
+          */
+         unsigned explicit_offset:1;
+
          /** \name Layout qualifiers for GL_AMD_conservative_depth */
          /** \{ */
          unsigned depth_any:1;
@@ -448,6 +454,15 @@ struct ast_type_qualifier {
    int binding;
 
    /**
+    * Offset specified via GL_ARB_shader_atomic_counter's "offset"
+    * keyword.
+    *
+    * \note
+    * This field is only valid if \c explicit_offset is set.
+    */
+   int offset;
+
+   /**
     * Return true if and only if an interpolation qualifier is present.
     */
    bool has_interpolation() const;